The protocol is designed to test the hypothesis that a change in lipid peroxidation profile (LDL oxidation status, oxidation lag time LDL) changes significantly in patients pre and post methionine loading. Specifically, this protocol was targeted to patients with chronic renal failure who have a recognized tendency to develop accelerated atherosclerosis. We hypothesize that these patients-who have previously been demonstrated to have enhanced peroxidation following acute hyperhomocystinemia induced by methionine loading.